The present invention relates specifically to scarfed nozzles, an example of which can be found in the UK patent GB 2,163,105. In general the scarfed nozzle comprises a pair of relatively rotatable nozzle segments which co-operate to direct engine thrust in selective predetermined directions. Typically the vectoring range of these prior art nozzles is a function of the inclination of the scarfed nozzle plane relative to the nominal nozzle axis, the maximum value of which is fixed for a given nozzle length.
Prior art scarfed nozzles have been used in VTOL aircraft applications which utilize a single jet pipe nozzle to direct engine thrust in selective predetermined direction. In contrast, however, scarfed nozzles have failed to feature in any proposed VTOL aircraft having lift fan units coupled to vectorable nozzles for vertical thrust. The main reason for this has been nozzle stowability. In this type of application it is necessary, for aerodynamic reasons, to locate the lift fan units and associated nozzles within aircraft structure. For aerodynamic reasons also, it is necessary to limit the stowed nozzle length. Consequently, it is not always possible to achieve the required nozzle vectoring range without first compromising the airframe design in accordance with nozzle stowability.